TheRemainderIsAskedTermByTerm​(AngouriMath.​Entity,​AngouriMath.​Entity,​AngouriMath.​Entity.​Variable)

Whether the remainder after differentiating v, a special function of
a linear argument or a power of one, against u is asked term by term
when nothing answers it whole. Of a multiple of x, always. Of
a + b x, where the function's derivative divides by its argument -- Ei,
Si, Ci, Shi, Chi -- since the constant of the factor
integrated beside it is then matched to the linear and the terms are the case without
the offset; and where the function is integrated against itself, the square alone.
Not an error function of a + b x beside anything else: its derivative is a
Gaussian of the shifted argument rather than a quotient by it, a polynomial beside it
stays in every term, and asking them took the decline of (c + d x) erf(a + b x)^2 from six seconds to twenty-four, answering nothing.
https://github.com/asc-community/AngouriMath/issues/1501